Accordion pill comprising levodopa for an improved treatment of parkinson&#39;s disease symptoms

ABSTRACT

The invention provides for the use of an accordion pill comprising levodopa for the treatment of symptoms of Parkinson&#39;s disease in a subject in need thereof over a 24 hour period, to be administered to the subject in a twice daily administration regimen, with an interval of about 8 to about I 0 hours between the first dose and the second dose, and with an interval of about 14 to about 16 hours between the second dose and the first dose of the following day. The twice daily administration regimen provides a stable blood plasma level of levodopa in the subject after multiple administrations and is effective in treating the symptoms of Parkinson&#39;s disease over a 24 hour period.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a 35 U.S.C. §371 National Phase Entry Application ofInternational Application No. PCT/IB2011/002888 filed on Nov. 1, 2011,which designates the U.S., and which claims benefit of 35 U.S.C. §119(e)of U.S. Provisional Application No. 61/408,985 filed on Nov. 1, 2010,the contents of which are incorporated herein by reference in theirentireties.

FIELD OF THE INVENTION

The present invention relates to the use of multi-layered,biodegradable, gastroretentive drug formulations, known as the AccordionPill, for the controlled release of carbidopa/levodopa in an improvedmethod of treatment of Parkinson's Disease symptoms.

BACKGROUND OF THE INVENTION

Levodopa (LD) is the most effective drug for the symptomatic treatmentof Parkinson's disease (PD). No other medical or surgical therapycurrently available has been shown to provide anti-Parkinson benefitssuperior to what can be achieved with LD. However, following few yearsof LD treatment, the actions of each dose tend to wear off in themajority of PD patients. This wearing off between doses is stronglycorrelated to the drug's peripheral pharmacokinetic (PK) profile. Thepatients may find themselves during the day in either ON state, when thepatients are capable of normal movement, or in OFF state, wherein thepatients suffer from impaired movement. As the disease progresses, thepatients begin to fluctuate between the two states. These fluctuationsare often accompanied by troublesome diskinesias in ON state and deepOFF state, wherein movement is severely impaired. Hence, improvingconsistency of LD's plasma levels is essential for improving itsanti-Parkinson effects.

In addition, in current treatment, physicians fractionate LD doses in anattempt to reduce the pulsed action of fewer, larger doses, and tostabilize the LD's pharmacokinetic (PK) profile. Hence, a significantpill burden is another major concern, associated with LD treatment.Advanced PD patients often take up to 8-10 LD doses a day, trying tostabilize their motor conditions.

For these reasons, numerous efforts have been made by manypharmaceutical companies over the years to develop an effectivelong-acting LD. Available controlled-release preparations of LDcurrently on the market do not maintain sufficiently high LD plasmalevels. The reason is that in addition to its very short half-life (90min), LD is absorbed mainly in the upper part of the GI tract. Once atypical controlled-release formulation has passed the drug's narrowabsorption window in the upper part of the GI, the drug is no longerabsorbed in the distal intestine, regardless of the manner it isreleased from the dosage form.

Another concern with current LD treatment is that rapid elimination ofLD and lack of means to sustain relevant LD levels for prolonged timeintervals lead to the absence of sufficiently high LD plasma levels inpatients in the morning, causing movement arrest and necessitatingultra-rapid LD dosage forms, generally unavailable on the market, orparenteral preparations which are cumbersome for self administration indeep OFF state.

The symptoms of PD in patients are frequently expressed as UnifiedParkinson's Disease Rating Scale (UPDRS) score. Most frequently,so-called “part 3” is used in evaluation by a clinician of motorabilities/impairment of PD patients. The UPDRS was recently reviewed andupdated, and is regarded as a standard mean to evaluate PD patients (seeMovement Disorders, Vol. 22, No. 1, 2007, pp. 41-47; Movement DisorderSociety-Sponsored Revision of the Unified Parkinson's Disease RatingScale (MDS-UPDRS): Process, Format, and Clinimetric Testing Plan, by Dr.Christopher G. Goetz et al, doi: 10.1002/mds.21198).

It is postulated that gastric retention could significantly prolong theLD's absorption phase, by retaining the drug in proximity to itsabsorption site and releasing the drug in a continuous manner, towardsthat absorption site. Some examples of gastroretentive LD deliverysystems are disclosed in WO2009/144558 (Intec Pharma), which is hereinincorporated by reference in its entirety. These gastroretentiveformulations are also frequently referred to as “Accordion Pill”, or AP.Alternatively, some gastric retentive pharmaceutical compositions fortreatment and prevention of CNS disorders are disclosed in WO2010/019915(Depomed).

Hence, the challenge is to develop an oral, effective long-acting LDregimen that provides significantly more continuous and stable relevantLD plasma levels over 24 hours, with reduced Total OFF Time andsignificantly reduced doses per day, preferably a twice-daily dosing.

SUMMARY OF THE INVENTION

The present invention is directed to overcoming the problems of theprior art described above.

Thus, in one embodiment, the invention provides for the use of anaccordion pill comprising levodopa for the treatment of symptoms ofParkinson's disease in a subject in need thereof over a 24 hour period.The accordion pill comprising levodopa is administered to the subject ina twice daily administration regimen, as a first dose and as a seconddose, with an interval of about 8 to about 10 hours between the firstdose and the second dose, and with an interval of about 14 to about 16hours between the second dose and the first dose of the following day.In a preferred aspect of the invention, the twice daily administrationregimen provides a stable blood plasma level of levodopa in the subjectafter multiple administrations. In an even more preferred aspect of theinvention, the stable blood plasma levels of levodopa are effective intreating the symptoms of Parkinson's disease over a 24 hour periodfollowing the administration of the first dose.

In one embodiment, the accordion pill comprises about 250 mg levodopa,and the twice daily administration regimen provides after multipleadministrations average blood plasma levels of levodopa of 200-1,000ng/ml in the subject over a 24 hour period following administration ofthe first dose.

In a different embodiment, the accordion pill comprises about 375 mglevodopa, and wherein the twice daily administration regimen providesafter multiple administrations average blood plasma levels of levodopaof 500-1,500 ng/ml in the subject over a 24 hour period followingadministration of the first dose.

In yet another embodiment, the accordion pill comprises about 500 mglevodopa, and the twice daily administration regimen provides aftermultiple administrations average blood plasma levels of levodopa of700-2,000 ng/ml in the subject over a 24 hour period followingadministration of the first dose.

In some embodiments, the accordion pill of the twice dailyadministration regimen provides absorption of levodopa into the bloodplasma of the subject for about 6 to about 14 hours followingadministration of the accordion pill.

In one aspect of the invention, the twice daily administration regimenfurther comprises administering to the subject one or more dosage formscomprising immediate-release or controlled-release levodopa.

In a preferred embodiment, the stable blood plasma level of levodopa inthe subject provides an absolute peak-to-trough ratio of levodopa bloodplasma concentrations below 7.

In another preferred embodiment, the twice daily administration regimenreduces peak-to trough fluctuations in the blood plasma levels oflevodopa in the subject by at least 50% in comparison toimmediate-release formulations comprising daily equal-doses administeredfour times a day.

In one aspect of the invention, the twice daily administration regimenshortens or eliminates total OFF time during waking hours in thesubject. In a different aspect of the invention, the twice dailyadministration regimen allows faster onset of the ON period in thesubject.

In a preferred embodiment, the twice daily administration regimenalleviates or eliminates nightly sleep disturbances and daytimesleepiness or drowsiness in the subject.

In a different aspect of the invention, the twice daily administrationregimen further comprises administering to the subject one or moreadd-on dosage forms comprising immediate-release or controlled-releaselevodopa.

In an additional embodiment, the invention provides for the use of anaccordion pill comprising levodopa for the treatment of symptoms ofParkinson's disease in a subject in need thereof over a 24 hour period.The accordion pill comprising levodopa is administered to the subject ina twice daily administration regimen, with an interval of about 8 toabout 10 hours between the first dose and the second dose, and with aninterval of about 14 to about 16 hours between the second dose and thefirst dose of the following day.

Preferably, the twice daily administration regimen provides a stableblood plasma level of levodopa in the subject after multipleadministrations. In a preferred aspect of the invention, the stableblood plasma level of levodopa in the subject is effective in treatingthe symptoms of Parkinson's disease over a 24 hour period following theadministration of the first dose.

In an even more preferred aspect of the invention, the twice dailyadministration regimen of the invention produces significantly highmorning levels of levodopa in the blood plasma of the subject.Preferably, the significantly high morning levels of levodopa in theblood plasma of the subject allow faster onset of the ON period orshorten the OFF period after the first levodopa administration of theday.

In one preferred aspect of the invention, the twice daily administrationregimen alleviates or eliminates nightly sleep disturbances and daytimesleepiness or drowsiness in the subject.

In one embodiment, the accordion pill comprises about 250 mg levodopa,and the twice daily administration regimen provides after multipleadministrations average blood plasma levels of levodopa of 200-1.000ng/ml in the subject over a 24 hour period following administration ofthe first dose.

In a different embodiment, the accordion pill comprises about 375 mglevodopa, and wherein the twice daily administration regimen providesafter multiple administrations average blood plasma levels of levodopaof 500-1,500 ng/ml in the subject over a 24 hour period followingadministration of the first dose.

In yet another embodiment, the accordion pill comprises about 500 mglevodopa, and the twice daily administration regimen provides aftermultiple administrations average blood plasma levels of levodopa of700-2,000 ng/ml in the subject over a 24 hour period followingadministration of the first dose.

In one aspect of the invention, the accordion pill may further compriseabout 50 mg to about 75 mg of carbidopa. In a preferred aspect of theinvention, the twice daily administration regimen provides carbidopablood plasma levels sufficient to adequately prevent peripheral levodopaside effects in the subject for a 24 hour period.

In a preferred aspect of the invention, the stable blood plasma level oflevodopa in the subject after multiple administrations provides valuesof area-under-the-curve over 24 hours and a relative bioavailabilitythat is not less than 85% relative to the values obtained fromimmediate-release formulations comprising daily equal doses administeredfour times a day. Alternatively, the stable blood plasma levels oflevodopa in the subject after a single administration provides values ofarea-under-the-curve extrapolated to infinity and a relativebioavailability that is not less than 85% relative to the valuesobtained from immediate-release formulations comprising equal doses oflevodopa.

In preferred embodiments, the twice daily administration regimen of theinvention after multiple administrations provides a reduction of totalOFF time during waking hours from about 3 hours to about 1 hour.Alternatively, the twice daily administration regimen of the inventionafter multiple administrations provides a reduction in total OFF timeduring waking hours of not less than 50% in comparison to the total OFFtime associated with the administration of optimized prior treatment ofthe subject with levodopa.

In yet a different aspect, the invention provides for the use of anaccordion pill comprising levodopa for the treatment of symptomsresponsive to levodopa in a subjects in need thereof over a nocturnalperiod. The accordion pill comprising levodopa is preferablyadministered at bed time. In a preferred aspect of the invention, bedtime administration improves sleep quality during the night followingadministration. In an even more preferred aspect of the invention, bedtime administration alleviates or eliminates the symptoms of morningakinesia or morning dystonia.

The foregoing general description and the detailed description areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed. Other objects, advantages, andnovel features will be readily apparent to those skilled in the art fromthe following detailed description of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 presents the results of a pharmacokinetic equidose study in earlyPD patients with AP CD/LD 50/250 mg, administered b.i.d vs IR q.i.d.

FIG. 2 presents the results of a pharmacokinetic equidose study inadvanced PD patients with AP CD/LD 50/375 mg, administered b.i.d vs IRq.i.d.

FIG. 3 presents the results of a pharmacokinetic equidose study inhealthy volunteers with AP CD/LD 50/500 mg, administered qd (once) vs IRb.i.d.

FIG. 4 presents the levodopa absorption profile as percentage of totalbioavailable dose, as calculated from the data of the example 2.

FIG. 5 presents strong correlation between steady LD blood plasma levelsand elevated UPDRS scores of the patients—AP-CD/LD-50/375 mg.

DETAILED DESCRIPTION OF THE INVENTION Definitions

“Gastroretentive dosage form”, or “Accordion Pill”, or “AP”, as usedinterchangeably herein refers to dosage forms with delayed gastricemptying as compared to food or to regular oral drug formulations (orretention in the stomach beyond the retention of food). In particular,the term refers to a multilayered gastroretentive dosage form, foldedinto a capsule in undulated form, which unfolds upon contact with thegastric fluids.

The term “degradable” as used herein is intended as capable of beingchemically and/or physically reduced, dissolved or broken down in thebody of a patient and within a relevant time period.

A “patient” or “subject” as referenced herein is a human or non-humanmammal suffering from symptoms of Parkinson's disease or of a relateddisorder.

“Treating” or “treatment”, are used herein to refer to obtaining adesired pharmacological and physiological effect. The effect may beprophylactic in terms of preventing or partially preventing a disease,symptom or pathological condition and/or may be therapeutic in terms ofa partial or complete cure of a disease, condition, symptom or adverseeffect attributed to a pathological condition. Thus, “treatment” coversany treatment of a disease in a mammal, particularly a human, andincludes: (a) preventing a pathological condition from occurring in anindividual which may be predisposed to develop a pathological conditionbut has not yet been diagnosed as having it, i.e., causing the clinicalsymptoms of a pathological condition not to develop in a subject thatmay be predisposed to develop the condition but does not yet experienceor display symptoms of the condition; (b) inhibiting, i.e., arresting orreducing the development of the pathological condition or its clinicalsymptoms; or (c) relieving symptoms associating with the pathologicalcondition. In particular, the term refers to alleviating symptoms ofParkinson's disease and of related movement disorders, clinicallyresponsive to levodopa.

“About” as used herein generally refers to approximate values. Whenreferred to a dose of LD in milligrams, “about” should be construed asincluding the range of a value ±50 mg. When referred to time intervalsof dose administration, “about” should be construed as including therange of a value ±1.0 hour. When referred to pharmacodynamic values oftotal ON or total OFF time, during waking hours or over 24 hours, theterm should be construed as including the range of a value ±0.15 hour.When referred to blood plasma levels of LD and other values, the termshould be construed as including the range of a value ±15%

The term “equidose”, or “equal-dose”, as used interchangeably herein,refers to as containing the same total dose of an active material,administered over the dosing regimen, particularly, over 24 hoursperiods.

“Add-on dose”, or “rescue dose”, as used interchangeably herein, referto a medicinal product comprising levodopa. An add-on dose providesadditional levodopa to the regimen of the present invention. Sometimesadd-on doses are taken by the patients to expedite the arrival to ONstate. The term should be construed as including an immediate-releaseproduct comprising levodopa, or a controlled-release product, comprisinglevodopa.

“Effective LD blood plasma levels”, as used herein, refer to LD levelsthat provide the desired pharmacodynamic effect in a subject in need oftreatment with minimal side effects. For early non-fluctuating PDpatients the effective LD blood plasma levels are usually not less thanabout 200 ng/ml at any point of time for 24 hours after administrationof a first dose of the regimen. The effective LD blood plasma levelsusually do not exceed about 1000 ng/ml. In more advanced non-fluctuatingPD patients, the effective LD blood plasma levels are usually not lessthan about 300 ng/ml, and preferably above about 500 ng/ml, and do notexceed about 1500 ng/ml. In fluctuating PD patients, the effective LDblood plasma levels are usually greater than about 500 ng/ml, andpreferably greater than about 700 ng/ml, and do not exceed about 2000ng/ml over a 24-hours period after administration of a first dose of theregimen.

“Significantly High Morning LD levels”, as used herein, are the LDlevels achieved by PD patients as a result of multiple administrationsaccording to the regimen of the invention about 0.5 hour or just priorto administration of the first dose of the consecutive treatment day. Inearly non-fluctuating patients these levels are usually above about 200ng/ml. In more advanced non-fluctuating PD patients, the significantlyhigh morning LD levels are not less than about 300 ng/ml and preferablyabove about 500 ng/ml. In fluctuating PD patients, the significantlyhigh morning LD levels are above about 500 ng/ml, and preferably aboveabout 700 ng/ml. The term is used as opposed to “significantly lowmorning LD levels”, which should be construed as confined to the valuessignificantly below the above described.

“Relevant therapeutic LD levels throughout the night” and “Significantnight levels of LD”, as used interchangeably herein, are effectivenocturnal LD blood plasma levels that lead to significantly high morningLD levels.

“LD Elimination Half Life”, as used herein, is a pharmacokineticparameter as known in the art, and represents the time required forlevodopa blood plasma concentration to decrease to half of its initialvalue in absence of input of levodopa to the bloodstream.

“Short Absorption phase”, as used herein, is an absorption phase havinga duration of less than 14 hours, and preferably less than 6 hours.

“Long arrival to ON state” and “Long duration of OFF time uponadministration of a subsequent dose”, as used interchangeably herein,relate to the buildup of LD blood plasma levels required forconventional formulations for arrival usually from significantly lowmorning LD levels to effective LD blood plasma levels, as opposed to the“Quick arrival to ON state” and “Faster onset of the ON period”, as usedinterchangeably herein, which refer usually to the arrival fromsignificantly high morning LD levels to effective LD blood plasmalevels, said arrival does not require significant buildup of LD bloodplasma levels. More specifically, the terms refer to the time intervalsrequired for a patient to reach ON state following the firstadministration of LD of the day.

“Morning OFF time”, as used herein, refers to the time interval betweenthe administration to a PD subject LD and the subject's arrival to ONstate following the administration. Morning OFF time is usuallyassociated with significantly low morning LD blood plasma levels.

“Repetitive dosing”, or “multiple administrations”, as usedinterchangeably herein, refers to repetitive administration of LDaccording to a specified dosing regimen, for period over more than oneday.

Induce rapidly ON state—as used herein, refers to a process of rapidarrival to ON state, usually as a consequence of administration of anadd-on dose of levodopa, an immediate-release dose of levodopa, orprematurely taking a consecutive dose of a treatment. In the descriptionherein, the term usually refers to current treatment regimens oflevodopa.

“Peak-to-trough ratio”, as used herein, refers to the ratio between thepeak concentration of the regimen (Cmax) and the trough concentration ofthe regimen (Cmin) over 24 hours period.

“Absolute fluctuation”, as used herein, refers to the mathematicaldifference between the peak concentration of the regimen (Cmax) and thetrough concentration of the regimen (Cmin) over 24 hours period.

“Total OFF time”, as used herein, refers to the duration of total of allOFF episodes over a specified time interval, either during waking hours,or over 24 hours.

“Total ON time”, as used herein, refers to the overall duration of allON episodes over a specified time interval, either during waking hours,or over 24 hours.

“Significant Reduction”, as used herein, refers to a statisticallysignificant reduction as measured by ANOVA test (α=0.05) (P value below0.05).

“Better sleep quality”, as used herein, refers to improved sleepquality, defined by fewer mid-night awakenings, increased total sleeptime and extended depth of sleep.

The Accordion Pill (AP)

The Accordion Pill (AP) is a dosage form designed to significantlyincrease efficacy and/or to reduce adverse drug reactions (ADRs) and/orfrequent daily dosing of drugs that are characterized by poor absorptionin the colon or which absorption is confined to yet narrower sites. TheAP is retained in the stomach and releases the drug in a predeterminedrelease profile, enabling a prolonged exposure to the absorption area inthe upper part of the small intestine, hence—to significantly prolongthe actual absorption phase of the drug.

The Accordion Pill is composed of degradable pharmaceutically acceptablepolymeric films. The films are layered sandwich style and are folded inan undulated structure, like an accordion, into a standard capsule.After oral administration, the capsule dissolves and the dosage formunfolds and is retained in the stomach. While in the stomach, theAccordion Pill releases the active ingredients in a predeterminedrelease profile (controlled release or combination of immediate andcontrolled release). Once the AP is expelled from the stomach andreaches the intestines, it degrades m the higher pH and within a fewhours it totally dissolves.

Certain delivery systems of AP-CD/LD are disclosed in WO2009/144558,which is herein incorporated by reference in its entirety.

In preferred embodiments, the AP-CD/LD comprises an internal layer, oneor more outer membranes, preferably two, sandwiching said internallayer, all said layers being ultrasonically welded together.

The internal layer comprises levodopa and a polymer, substantiallyuniformly distributed throughout the internal layer. The polymer may beselected from the group consisting of a degradable hydrophilic polymerwhich is not instantly soluble in gastric fluid, a degradable entericpolymer which is substantially insoluble at pH less than 5.5, ahydrophobic polymer, or mixtures thereof. Said internal layer mayfurther comprise acceptable pharmaceutical additives, such asplasticizers, humectants, fillers and others. Examples of such additivesare provided in various sources in the art, for example in the “Handbookof pharmaceutical excipients”, edited by Rowe, Ray C; Sheskey, Paul J;Quinn, Marian, printed by Pharmaceutical Press. Examples of degradablehydrophilic polymers which are not instantly soluble in gastric fluidsuitable for the invention include but not limited to hydroxypropylcellulose, hydroxypropylmethyl cellulose, polyvinyl pyrrolidone,copovidone, polyethylene oxide, poloxamers and methylcellulose. Examplesof the enteric polymers include but not limited to polymethacrylatecopolymers, cellulose acetate phthalate, hypromelose acetate succinateor hypromellose phthalate. Examples of hydrophobic polymers include butnot limited to ethyl cellulose, cellulose acetate, cellulose butyrateand polyvinyl acetate. In further preferred embodiments, the internallayer comprises levodopa, an enteric polymer, a degradable hydrophilicpolymer which is not instantly soluble in gastric fluid and aplasticizer. In further preferred embodiments, the enteric polymer ispolymethacrylate copolymer—methacrylic acid copolymer type A ormethacrylic acid copolymer type B, as defined in the United StatesPharmacopea 34/National Formulary 29 (USP/NF). These materials are alsoknown under newer specifications of the USP/NF as “methacrylic acid andmethyl methacrylate copolymer (1:1)”, and “methacrylic acid and methylmethacrylate copolymer (1:2)”, respectively. In another preferredembodiment, the plasticizer is a mixture of polyethylene glycol and apoloxamer. In yet further preferred embodiments, the internal layerprovides substantial mechanical strength.

Each of the outer membranes of the AP-CD/LD comprises at least onepolymeric combination of a hydrophilic polymer and a polymer, insolublein gastric media, and at least one plasticizer. Examples of hydrophilicpolymers include but not limited to gelatin, hydroxypropylcellulose,hydroxypopyl methycellulose, pectin, polyethylene oxide, starch, andzein. In preferred embodiments, the hydrophilic polymer is gelatin. Theenteric polymers suitable for the outer membranes include but notlimited to hypromellose phthalate, hypromellose acetate succinate andpolymethacrylate co-polymers. In preferred embodiments, the entericpolymer is polymethacrylate copolymer—methacrylic acid copolymer type Aor methacrylic acid copolymer type C, as defined in the USP/NF, or,under newer definitions, “methacrylic acid and methyl methacrylatecopolymer (1:1)” and “methacrylic acid and ethyl acrylate copolymer(1:1)”. Plasticizers suitable for the outer membrane include but notlimited to glycols, including various MW polyethylene glycols, glycerin,poloxamers, triethyl citrate, or a mixture of any of the above. In apreferred embodiment, the plasticizer is propylene glycol. In anotherpreferred embodiment, the plasticizer is a mixture of polyethyleneglycol and poloxamer.

In various embodiments, the outer membranes swell in the presence ofgastric fluid.

In preferred embodiments, the internal layer and two outer layers arejoined together by ultrasonic welding. The combination of swelling outermembrane layers with a non-swelling internal layer having planaraccordion geometry causes the internal layer to undergo an unfoldingprocess once the formulation reaches the stomach, thus extending gastricresidence time and preventing the drug-containing dosage form from beingevacuated until complete release. In some embodiments the internal layerhas a swelling rate less than the swelling rate of the membrane.

In some embodiments, the AP-CD/LD comprises an internal layer and atleast two outer membranes as described above, and may further compriseadditionally one or more immediate release layers covering the outermembranes and comprising the active agent and a composition thatprovides for the immediate release of the active agent. In someembodiments, the additional layer comprises levodopa. In otherembodiments, said additional layer comprises carbidopa. In preferredembodiments, two additional layers are provided covering both outermembranes, wherein a first additional layer comprises levodopa, and asecond additional layer comprises carbidopa. Said composition maycomprise soluble polymers, enteric polymers, plasticizers,disintegrants, surface-active agents and other pharmaceuticalexcipients, as described above.

In several embodiments, the soluble polymers of said composition for theuse in said additional layers include but not limited to solublecellulose derivatives, i.e. methyl cellulose, hydroxypropyl cellulose,hydroxyethyl cellulose, hypromelose, various grades of povidone,including copovidone, polyvinyl alcohol and its derivatives, i.e.Kollicoat IR, soluble gums and others. The composition for the use insaid additional layers may further include surface-active agents,plasticizers and humectants, such as PEGs, different grades ofpolysorbates and sodium lauryl sulfate. In several embodiments, theenteric polymers of said composition for the use in said additionallayers include but not limited to polymethacrylate copolymers,hypromellose phthalate, hypromellose acetate succinate, celluloseacetate phthalate, or a mixture thereof. In preferred embodiments, thepolymer is methacrylic acid copolymer type C, also known as “methacrylicacid and ethyl acrylate copolymer (1:1)”, as described in the USP/NF. Inseveral preferred embodiments, said composition further comprises adisintegrant. Disintegrants imbibe water upon contact and swell rapidlyto provide separation of the adjacent parts. The disintegrant of saidcomposition for the use in said additional layers is crospovidone,croscarmellose, sodium starch glycolate, or mixtures of the above. Inpreferred embodiments, the disintegrant is sodium starch glycolate.

In further embodiments, the AP-CD/LD may further comprise an optionaladditional layer covering each outer membrane or each additional layerand comprising a powder or a film. The purpose of the layer is to avoidadhesion of the folds of the undulated form of AP-CD/LD uponcapsulation, and the adhesion of the folds to the capsule. In someinstances it may be found that the outer layers stick together in thecapsule and do not unfold properly upon dissolving of the capsule. Inpreferred embodiments, said optional layer comprises at least onepowder, and optionally at least one polymer. In other embodiments thepreferred polymers are rapidly-dissolving film formers, which can beselected from but not limited to soluble cellulose derivatives, i.e.methyl cellulose, hydroxypropyl cellulose, hydroxyethyl cellulose,hypromelose; various grades of povidone; polyvinyl alcohol and itsderivatives, i.e. Kollicoat IR; soluble gums and others. The films mayfurther comprise surface-active agents, plasticizers and humectants. Thepowders that may be used in said optional layer include but not limitedto microcrystalline cellulose, talc, silica, colloidal silicon dioxide,a clay or a mixture of any of the above. In preferred embodiments, saidoptional layer comprises microcrystalline cellulose.

In all embodiments of the present invention, the AP-CD/LD is folded intoundulated form and compacted into a standard pharmaceutical capsule.

The Dosing Regimen

The present invention provides a twice daily administration regimen ofAP-CD/LD formulations in doses such as, for example, a 50/250 mg dosageform, targeted for early stage PD patients; 50/500 or 50/530 mg dosageforms targeted for advances stage PD patients; and 50/375 mg or 50/405mg dosage forms for treatment of both populations. In preferredembodiments, the twice daily administration regimen of the AP-CD/LDformulations of the invention provide effective blood plasma level oflevodopa for time intervals of about 24 hours, due to the absorptionphase, provided by AP-CD/LD, which is between about 6 to about 14 hours.In an even more preferred embodiment, of the absorption phase, providedby AP-CD/LD formulations of the invention are longer than 14 hours.

The length of the absorption phase is exemplified by the data presentedin the examples provided herein. Absorption data may be obtained fromthe concentration-vs-time curve by methods known in the art. Theseinclude modeling and de-convolution of functions, which describe theabsorption. One of the approaches is known as Wagner-Nelson approach.The analysis of the data presented in Example 2 using Wagner-Nelsonapproach yields an absorption curve, which is presented in FIG. 4. Thedoses were administered at time 0, and after 8 hours. FIG. 4 shows thatthe major absorption phase throughout the dosing regimen, for 24 hours,indicating individual absorption phases of over 6 hours, and over 14hours, exemplifying some of the preferred embodiments. Alternatively,the absorption phase may have duration of 6.5 hours, or 7.0, 7.5, 8.0,8.5, 9.0, 9.5, 10.0, 10.5, 11.0, 11.5, 12.0, 12.5, 13.0, 13.5, 14.0,14.5, 15.0, 15.5, or 16.0 hours.

In the use of the oral dosage forms of levodopa disclosed in theinvention, said dosage forms are administered twice a day, in a regimengenerally known as b.i.d. regimen. Conventionally, the b.i.d. regimen isconsidered as administration every 12 hours. In some embodiments of thepresent invention, the two doses are administered twice daily, every 12hours. However, in preferred embodiments of present invention, the twodoses of levodopa from the oral dosage form of the invention areadministered as a first administration of a day and a secondadministration of the same day, with an interval of about 8 to about 10hours between the first dose administration and the administration of asecond dose of levodopa, and with an interval of about 14 to about 16hours between the second dose of the first day and the first dose of thefollowing consecutive day. Whereas generally the preference is that thedescribed interval between the first administration and the secondadministration is 8 to 10 hours, the second dose can be administeredabout 6.0 hours after administration of the first dose, or 6.5 hours, or7.0 hours, or 7.5, hours, or 8.0 hours, or 8.5 hours, or 9.0 hours, or9.5 hours, or 10.0 hours, or 10.5 hours, or 11 hours afteradministration of the first dose. The regimen of administration of thetwo dosage forms according to the invention provides effective LD bloodplasma levels in the subject for 24 hour consecutive periods.Furthermore, repetitive administration of LD according to the specifieddosing regimen (“repetitive dosing”) provides stable effective LD bloodplasma levels in the subject for extended consecutive periods of timeand decreases or prevents fluctuations in the blood plasma level of LDin the subject. In all aspects and embodiments of the present invention,the repetitive dosing, or multiple administrations, are referred to aperiod having duration of more than one day, for example, 2 days, 3days, 4, 5, or 6 days, 1 week, 2 weeks or 3 weeks, 1 month, 1.5 months,2 months, or 3 months. In principle, said twice-daily treatment regimenof the present invention may be continued in the same or varied dosingand intervals for as long as benefit to a patient is sustained.

Sleep quality is another major issue in PD. Entering into OFF stateduring the sleep leads to awakening of the patients, and poses a problemto fall asleep again. As shown in the examples of the presentapplication, the regimen of administration of the two dosage formsaccording to the invention results in morning LD levels in the bloodplasma of a patient that are significantly higher than the morning bloodplasma LD levels provided by known current treatment methods. Thesignificantly high morning blood plasma LD levels that the inventionprovides indicate that the administration regimen of the inventionmaintains therapeutic LD levels in the blood plasma of the subject beingtreated throughout the night, and leads to clinically relevant, stableconcentrations of LD in the blood plasma of the subject. In turn, theretention of therapeutic LD levels throughout the night improves qualityof sleep and reduces day time sleepiness in the subject being treated.

Normally, LD does not reach continuously effective LD blood plasma levelwhen administered as immediate or controlled-release dosage forms, dueto LD short elimination half-life and short absorption phase provided bythese dosage forms; the parameters are not sufficiently increased byconventional controlled-release dosage forms. As a result, conventionalregimens do not afford significant blood plasma night levels of LD,thereby reducing quality of sleep, and as a result causing daysleepiness and drowsiness, as described above. In addition, the lack oftherapeutic LD blood plasma levels throughout the night leads to lowmorning LD blood plasma levels, significantly prolongs the duration ofOFF time upon administration of a subsequent dose the next day, andresults in a delayed arrival to the ON state, because the processrequires a large LD blood plasma level buildup to reach the ON state.Frequently, to overcome the problem, the patients use high doses of IRlevodopa, thus increasing fluctuations of blood plasma levels of LD.

The twice daily administration regimen of the invention, wherein the twoLD doses are administered with an interval of about 8 to about 10 hoursbetween the first dose of a day and the second dose of the same day, andwith an interval of about 14 to about 16 hours between the second LDdose of the first day and the first LD dose of the following consecutiveday, affords effective night levels and thus reduces, alleviates orpotentially eliminates nightly sleep disturbances and daytime sleepinessor drowsiness, which are major issues in subjects suffering fromParkinson's disease. Furthermore, the twice daily administration regimenof the invention produces significantly high morning levels of LD,shortens or eliminates morning OFF time, and, because of thesignificantly high morning levels of LD, results in a quicker arrival tothe ON state upon administration of the first dose in the consecutivemorning, since the process does not require LD blood plasma levelbuildup to reach the ON state. Upon a particular need, regular orreduced doses of LD can be used to arrive quickly to ON state.

LD is released from the oral dosage forms administered according to theregimen of the invention providing relatively stable LD blood plasmalevels in the subjects being treated for extended periods of time.Surprisingly, the LD blood plasma levels are sustained for 24 hours inthe subject after repetitive dosing according to the regimen. In oneembodiment, the dose of LD in the oral dosage form is about 250 mg, andunder the b.i.d. regimen of 8-10 h, as described above, the blood plasmain the subject being treated reaches a stable LD level of 200-1,000ng/ml. The blood plasma levels of levodopa would be therefore generallymore than about 200 ng/ml, or 180, 200, 220, 240, 250, 260, 280 or 300ng/ml, and generally less than 1000 ng/ml, or 980, 950, 925, 900, or 875ng/ml. In another embodiment, the dose of LD in the oral dosage form isabout 375 to about 405 mg, and the blood plasma of the subject beingtreated reaches a stable LD level of about 500-1,500 ng/ml. The bloodplasma levels of levodopa would be therefore generally more than about500 ng/ml, or 450, 475, 500, 525, 550, 575, 600, 650 or 700 ng/ml, andgenerally less than 1500 ng/ml, or 1475, 1450, 1425, 1400, 1350, or 1300ng/ml. In yet another embodiment, the dose of LD in the oral dosage formis from about 500 to about 530 mg, and the blood plasma of the subjectbeing treated reaches a stable LD level of about 700-2,000 ng/ml. Theblood plasma levels of levodopa would be therefore generally more thanabout 700 ng/ml, or 625, 650, 675, 700, 725, 750, 775, 800, 825 or 850ng/ml, and generally less than 2000 ng/ml, or 1950, 1925, 1900, 1875,1850, 1825 or 1800 ng/ml.

In one aspect of the invention, the two oral dosage forms administeredaccording to the regimen of the invention contain the same dose of LD.In alternative embodiments, the doses are different to accommodate theneeds of the patient in either the first part of the day or the secondpart of the day. One patient may require higher levels in the afternoon,whereas another may require higher levels in the first part of the day.The doses can be varied by the prescriber to obtain optimal efficacyover 24 hours, according to individual needs of the patients. This givesrise to asymmetrical regimens, whereby the first dose is not necessarilyequal to the second. In alternating multiple embodiments, there are manysuch combinations possible, exemplified but not limited to 250 mg in themorning and 250 mg in the afternoon, 250 mg in the morning and 375 mg inthe afternoon, 375 mg in the morning and 500 mg in the afternoon, 250 mgin the morning and 500 mg in the afternoon, or 500 mg in the morning and375 mg in the afternoon. Any such or similar combination represents thebasal treatment regimen and provide treatment of Parkinson's diseasesymptoms over 24 hours, when administered to a patient in need thereofin an interval of about 8 to 10 hours, after repetitive dosing, therebyproviding stable efficacious blood plasma levels of LD.

The treatment provided according to the regimen of the invention may beoptionally enhanced by administration of “add-on” doses. These comprisedosage forms comprising LD for either immediate release (IR), orcontrolled release (CR), or a combination thereof. The need for theseadd-on doses arises from inevitable intra-subject variability, meaningthat the same subject may not react the same way to the same dosage formadministered on a different day. This intra-subject variability inday-to-day response to LD is well-known in PD treatment. The add-ondoses are vastly used in current treatment schedules to induce rapidlyON state and to end OFF state. The current regimens overburden thepatients with the doses of LD. The disclosed regimen overcomes thisproblem, as it cumulatively requires substantially fewer number of LDdoses per day, than needed with current treatments. Therefore, in someembodiments, said twice-daily regimen further comprises administrationof one or more add-on LD doses. In some embodiments, said add-on dosesare immediate-release doses. In alternative embodiments, said add-ondoses are controlled release doses. In other embodiments, said dosescomprise mixed immediate-release and controlled-release doses. Inseveral embodiments, said doses are administered on the same time everytreatment day. Alternatively, said add-on doses may be administered asneeded on varying time during the treatment day.

Conventional dosing regimens frequently result in high fluctuations. Thepeak-to-trough ratio is usually used to evaluate the fluctuations ofblood plasma levels of a drug. Alternatively, when comparing dosingregimens, sometimes absolute fluctuation values are used to express thedegree of change that certain dosage form produces. Fluctuations oflevodopa blood plasma levels in subjects treated with the conventionalformulations are very high, due to rapid elimination and limitedabsorption window of the conventional dosage forms.

The peak-to-trough ratio is calculated as maximal concentration achievedduring the 24-hours period, over minimal concentration over the sameperiod. Said ratio is 1 for continuous delivery dosage forms, such asintravenous infusion. Current treatment of immediate-release presentsratio of over 40. In several embodiments of the present invention, saidratio is below about 10, preferably below about 9.5, 9.0, 8.5, 8.0, 7.5,or 7. Alternatively, the fluctuations may be expressed by comparison tocurrent treatment, and the fluctuations produced by the twice-dailyregimen of the invention are reduced at least by about 50%, or by 44%,46%, 48%, 50%, 52%, 54%, 56%, 58%, 62% or 64% in comparison toconventional daily equal-dose IR treatment four times a day. Inpreferred embodiments, said fluctuations are reduced by about 60%.

The reduction in LD blood plasma fluctuations provided by the regimen ofthe invention decreases adverse effects associated with LD treatment.Most significantly, the total OFF time during waking hours decreases,and total ON time increases. The side effects are usually associatedwith more progressive stage of the disease. Administration of an oraldosage form of LD comprising about 375 mg or about 500 mg of LDaccording to the regimen of the invention with an interval of 8 to about10 hours between the first and the second dose to a patient in needthereof produces a significant reduction of total OFF time during wakinghours. Alternatively, two dosage forms, with an LD amount of 375 mg and500 mg, respectively, may be administered to a subject in need thereofaccording to the regimen of the invention for the treatment of symptomsof Parkinson's disease. Such administration leads to a significantreduction of total OFF time during the subject's waking hours.Similarly, the reduction of total OFF time in patients in need thereofcan be enhanced by incorporating into said regimen at least one add-on.Similarly to the described above, said add-on doses may comprise an IRlevodopa dose, a CR levodopa dose, or a mixture of the IR and CRlevodopa dose. The doses may be taken preferably as fixed-time dose, oralternatively, on “as needed” basis, as rescue dose for the interruptionor alleviation of the OFF state, thereby enhancing reduction of totalOFF time during waking hours. Alternatively, a method of treatment isprovided, for reduction or alleviation of Parkinson's disease symptomsin patients in need thereof, said method comprising administration anyof two oral dosage forms, comprising about 375 mg of LD, or about 500 mgof LD each, according to the regimen of the invention, which methodfurther comprises administration of one or more add-on doses of IR or CRlevodopa.

The effectiveness of an anti-parkinson treatment is estimated asreduction in total OFF time, or as reduction of total OFF time duringwaking hours, sometimes used interchangeably. The total OFF time is animportant parameter and varies within the population of PD patients,according to the severity of the disease. Early patients have very shortperiods of OFF during the waking hours, or do not suffer at all from theOFF phenomenon. As the disease advances, the patients may reach totalOFF time of 0.5 hour to over 6.5 hours, and sometimes even to over 8.0hours. In yet more advanced stage, the patients reach these “total OFF”values even being treated adequately by best available regimens. Thetreatment provided according to the regimen of the inventionsignificantly reduces total OFF time. In some embodiments, the total OFFtime during waking hours is reduced by at least about 45%, but can bedecreased by 44%, 45%, 46%, 48%, 52%, 54%, 56%, 58%, 60%, 62% or by 64%,versus either baseline values or versus the optimized LD treatment of asubject. In other preferred embodiment, the treatment provided accordingto the regimen of invention reduces total OFF time by at least 1.2hours, but can be decreased by 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2,1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6,2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0,4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, or by 5.0 hours. In furtherpreferred embodiments, the regimen of present invention provides areduction in total OFF time during waking hours from 2.9 hours to 1.2hours, versus optimized levodopa treatment in the subject. In yetfurther preferred embodiments, the reduction is obtained byadministering to the patient in need the AP-CD/LD 375 mg twice daily,according to the regimen of the invention, without or practicallywithout add-on doses (dosing frequency 2.2±0.2 per 24 hours).

Conventional regimens of LD treatment do not provide the subject beingtreated with significantly high morning levels of LD, as describedabove. Moreover, PD patients frequently suffer from night OFF state,whereby the patients are awakened by their incapacity to move duringtheir sleep. This sometimes results in the need to take nocturnal LDdoses. These subjects suffer from drowsiness and daytime sleepiness, asa result of night awakening. The overall quality of life of thesepatients may deteriorate. Taking higher LD doses at bedtime does notsolve the problem, as LD is rapidly removed from the bloodstream and itsabsorption is limited to a maximum of two hours of the narrow absorptionwindow. Moreover, taking overdoses of LD can result in troublesomediskinesias, expressed by involuntary movements, which further impedefalling asleep and offer no solution. A large number of subjectsaffected by PD and facing fluctuations in their blood plasma LD levelare thus compelled to use sleep-inducing medicines, which further burdenthe patient with yet a higher pill-load and increases the risk ofdrug-to-drug interactions.

The treatment regimen of the present invention resolves these issues byproviding high blood plasma LD levels in the morning over 24 hourperiods in subjects in need of treatment of Parkinson's diseasesymptoms. The twice daily administration regimen of the invention,wherein the two LD doses are administered with an interval of about 8 toabout 10 hours between the first dose of a day and the second dose ofthe same day, and with an interval of about 14 to about 16 hours betweenthe second, pre-midnight LD dose of the first day and the first LD doseof the following consecutive day, provides the subjects being treatedwith stable, effective LD blood plasma concentrations for consecutive 24hour periods, affords effective LD night levels and thus reduces,alleviates or potentially eliminates nightly sleep disturbances anddaytime sleepiness or drowsiness, and produces significantly highmorning levels of LD. The high morning pre-dose LD blood plasma levelsprovided by the treatment regimen of the present invention alleviate oreliminate symptoms related to degenerative disorders of the centralnervous system, Parkinson's disease in particular, motor skills, speechand related impairments, prior to the subsequent administration of thenext day consecutive dose. In addition, the morning high LD blood plasmalevels provided by the treatment regimen of the present invention allowa faster onset of the ON period and shorten the OFF period after thenext day subsequent administration of the first dose. Moreover, themorning high LD blood plasma levels provided by the treatment regimen ofthe present invention result in better sleep quality throughout thenight and alleviate or eliminate daytime sleepiness and drowsiness onthe subsequent day.

In some embodiments, there is provided a use of an AP-CD/LD,administered to a patient in need thereof prior to going to sleep. Saidbedtime, or nocturnal administration provides effective LD blood plasmalevels throughout the night. In some embodiments, the dose should beadministered no later than 3 hours apart from the last LD dose of thepatient, but may be administered 1.25, 1.5, 1.75, 2.0, 2.25, 2.5, 2.75,3.0, 3.25, 3.5, 3.75, 4.0, 4.25, 4.50, 4.75 or 5.0 hours from theadministration of the last LD dose. In one aspect, the dose of levodopain AP-CD/LD is about 250 mg. In another aspect, the dose of levodopa inAP-CD/LD is about 375 mg. In yet another aspect, the dose of levodopa inAP-CD/LD is about 500 mg. In some embodiments, the nocturnaladministration of AP-CD/LD provides better sleep quality to the patientin need thereof. In other embodiments, the nocturnal administrationalleviates or eliminates morning akinesia symptoms in patients in needthereof.

Levodopa is usually administered with a DOPA-decarboxylaze inhibitor,such as benserazide or carbidopa. Normally, levodopa is co-administeredwith carbidopa. The art discloses several effective carbidopa/levodopacombinations with different ratios between the two. There is muchreasoning in favor of many ratios. Although there is a general consensusthat the total daily dose of carbidopa should not exceed 150-200 mg, PDsubjects are often treated with a vast variety of doses of LD that notalways have the same carbidopa/levodopa ratio. Many patients, especiallyadvanced PD patients, are prone therefore to reach the maximum alloweddaily carbidopa amounts under current treatment schedules. In contrast,the treatment regimen of the present invention supplies carbidopa insufficient quantity to provide a stable CD blood plasma concentrationfor 24 hour periods, regardless of the total LD daily dose administeredaccording to the treatment regimen. Moreover, even with thesupplementation of add-on dosages, the subject being treated accordingto the regimen of the invention will not exceed the maximum alloweddaily carbidopa amounts, as the regimen provides effective amounts ofcarbidopa to inhibit peripheral decarboxylaze activity sufficiently over24 hour periods. Studies show that peripheral DOPA decarboxylase issaturated by carbidopa at approximately 70 to 100 mg a day. Therefore insome preferred embodiments, the oral dosage forms administered accordingto the treatment regimen of the invention comprise carbidopa orpharmaceutically acceptable salt thereof, preferably in an amount fromabout 50 mg to about 75 mg of carbidopa each. Carbidopa is released fromthe dosage forms. In the treatment regimen of the present invention, thecarbidopa released upon absorption provides blood plasma levels ofcarbidopa that are sufficient to adequately prevent peripheral LD sideeffects for consecutive 24 hour periods.

When designing a treatment regimen, it is compulsory that the doses ofone dosing regimen be easily translated into another. It is well knownin the art that some controlled-release dosage forms provide lowerabsolute bioavailability than immediate-release doses, and thereforealso lower relative bioavailability in reference to the immediaterelease dose. This usually causes difficulties in transferring patientsfrom one treatment to another, as individual responses in patients areoften poorly predictable and one cannot lower bioavailability beforetrial and error. By providing stable LD blood plasma concentrationsafter repetitive dosing in a subject, the treatment regimen of thepresent invention affords a relative bioavailability which is not lessthan 95%, preferably not less than 90%, and even more preferably notless than 89%, 88%, 87%, 86%, or 85%. In preferred embodiments, thetreatment regimen of the present invention provides an area underconcentration-vs-time curve over 24 hour periods (AUC₀₋₂₄), and thus arelative bioavailability (F), which is not less than 95%, preferably notless than 90%, and even more preferably not less that 85%, of therelative bioavailability obtained with an equivalent dose regimen ofimmediate release dosage forms. Similarly, the treatment regimen of thepresent invention, after a single dose, provides an area underconcentration-vs-time curve extrapolated to infinity (AUC_(0-inf)), andconsequently, a relative bioavailability (F) which is not less than 89%,88%, 87%, 86%, or 85% of the AUC_(0-inf) obtained with an equivalentdose regimen of immediate release dosage forms.

In further aspect, the administration of said two doses is notrestricted to specific alimentary requirements. Usually, Parkinson'sdisease patients are advised to avoid high-protein food, high acidityfood and beverages, and are warned against delayed gastric emptying thatmight impede the action of conventional dosage forms of levodopa. Somelevodopa products even advise taking the medicine on empty stomach. Oncethe number of doses to be administered is low, the restriction can becomplied with. At higher dosing frequency, a patient may be required tofast for a significant portion of a day. Some dosage forms that canprovide benefit at three and more times a day administration, requirethe medicine to be taken with a meal, sometimes a meal of no less than750 kcal, whereof not less than 40% should be derived from fat. However,patients normally comply better with medications that do not requireextensive fasting or purposeful excessive eating.

In the administration of said two dosages of levodopa according to theregimen of the present invention, a small meal may be recommended beforethe administration. No excessive restrictions on diet are imposed bysaid regimen, providing a significant advantage to the patient. In someembodiments, the meals to accompany the first dosing of the dosage formshave calorie value of below 550 kcal, preferably below 540 kcal, orbelow 530, 500, 450, 400, 350, 300, 250, 200, or 191 kcal. In preferredembodiments, the meal has calorie value of 191 kcal, with 49% ofcalories being derived from fat. In further embodiments, the meals toaccompany the second dosing of the dosage forms have calorie value ofranging from about 430 kcal, to about 670 kcal, but can have the calorievalue of 450, 475, 500, 525, 550, 575, 600, 625, 650 or 670 kcal. Infurther embodiments, the calorie value derived from fat, of said mealaccompanying second administration of the regimen of the invention,comprise about 40%, or about 38%, 36%, 34%, 32%, or 30%. In furtherpreferred embodiments, the amount fat in the meals is an average amountof fat in alimentary products for human consumption.

Whereas levodopa is used vastly and primarily for treatment ofParkinson's disease symptoms, there arc conditions responsive tolevodopa, such as restless leg syndrome and others, that are notdirectly related to Parkinson's disease. All the disadvantages ofconventional regimens as disclosed above are valid for every othertreatment of conditions, responsive to levodopa. The treatment of nightsymptoms remains a significant challenge. Therefore, in someembodiments, there is provided use of an accordion pill comprisinglevodopa for the treatment of symptoms responsive to levodopa in asubject in need thereof over nocturnal period. In further embodiments,the AP-CD/LD is administered to the subject at or before bedtime. In yetfurther embodiments, said administration provides improvement in sleepquality in said subject over the night following administration. Invarious embodiments, the dose of levodopa in the AP-CD/LD is about 250mg, or about 375 mg, or about 500 mg. In other embodiments, there isprovided use of AP-CD/LD for alleviating or eliminating the symptoms ofmorning akinesia or morning dystonia.

The present invention, thus generally described, will be understood morereadily by reference to the following examples, which are provided byway of illustration and are not intended to be limiting of the presentinvention.

EXAMPLES Example 1 Phase IIA Included 12 Early Stage PD PatientsClinical Study Design:

A multi center, open, two-way randomized crossover, multiple dose,active control, pharmacokinetic study in Parkinson's patients that arenot experiencing wearing off, treated with low dose AP-CD/LD

The group was crossed over with a daily equidose of immediate release(IR) preparations of carbidopa/levodopa.

The Objectives

The primary objective was to evaluate the blood level profile of theAP-CD/LD relative to that of IR carbidopa/levodopa.

Another objective was to monitor the subjects for adverse events duringthe study period and to compare the safety of the test products with thereference products.

The Course of the Study

Subjects were randomized to start with either AP-CD/LD or with IR-CD/LD.The AP-CD/LD was dosed at 0 and 8 hrs on each day, for seven days. Thereference product was the commercially available 25/250 mg Dopicar®(Teva Pharmaceuticals) CD/LD immediate-release tablet (IR-CD/LD), whichwas administered four times a-day, as a ½ tablet (12.5/125) at 0, 4, 8and 12 hours on each day, for seven days. Since the amount of CD fromthe IR-CD/LD was half of that given by the AP-CD/LD and below therecommended amount of daily CD (70-100 mg), additional CD was given witheach dose during the pharmacokinetics (PK) evaluation day (day 7 of thecontrol treatment period). On the PK day Patients were co-administeredan additional 12.5 mg IR CD capsule with each Dopicar® dose to provide atotal CD dose of 100 mg. The total daily CD/LD doses for both productswere equivalent.

During days 1-6 of each period, the test and reference products wereself-administered at home every day. On the 7th day of dosing in eachperiod, patients were dosed in the clinic (PK day).

Within 7 days after the last PK day (days 15-22), the subjects underwentpost-study medical evaluation including blood and urine testing.

Each group was crossed over with an equal-dose of IR levodopa in arandomized manner.

AP-CD/LD 50/250 mg, Carbidopa/Levodopa Dosage Form

Amount/AP-CD/LD (mg) Immediate Internal layer Release Outer (sumControlled Component Layer of two films) release Carbidopa 25.0 25.0Levodopa 70.0 180.0 Eudragit S100 47.1 Eudragit L100 23.5 61.0 EudragitL100-55 23.5 Fish Gelatin 94.2 Propylene glycol 94.2 KOH 6.0 Poloxamer407 32.0 PEG 400 3.1 30.0 Tween 80 11.8 Povidone 90 13.7

Phase IIA, Subjects

Duration of Duration of Subject number Gender Age PD, (years) LD'sTreatment H&Y 102 M 68 3 6 months 2 104 M 73 2 9 months 2 106 M 74 2 3months 2 107 M 65 2 5 months 1.5 113 M 69 2 11 months  2 101 M 67 6 3years 2 103 M 76 7 7 years 2 105 M 76 9 3 years 2 108 M 71 11 6 years 2110 M 67 6 3 years 3 111 M 54 4 3 years 2 114 M 59 8 7 months 2

Results:

The results of primary objective (pharmacokinetic profile) are presentedin FIG. 1. True controlled-release profile of LD has been accomplished.BID administration of AP-CD/LD provided 15 monitored hours coverage of400-1,000 ng/ml LD plasma levels, and in fact 24 hours coverage profile,since significant morning levels were achieved.

BID administration of AP-CD/LD provided average plasma levels within therange that is currently obtained with four times a-day (equivalent totaldaily dose) LD formulation that is on the market, with substantiallyreduced peaks.

Morning starting plasma levels of LD from AP product were significantlyhigher than these from IR treatment (200 vs 30 ng/ml). This capabilityof AP-CD/LD can improve morning akinesia, improve sleep quality andreduce day time sleepiness.

Safety

No significant adverse effects were reported during the study.

Example 2 Phase IIB—12 Fluctuating PD Patients

The purpose of this study was to evaluate the efficacy (pharmacokineticsand pharmacodynamics) and the safety of AP-CD/LD 50/375 mg, in variousgroups of advanced PD patients, after multiple dosing, in comparison toCD/LD formulations, currently on the market.

Clinical Study Design

A multi center, open, two-way randomized crossover, multiple dose,active control, pharmacokinetic and pharmacodynamic study in patientswith wearing off treated with high dose AP-CD/LD.

The group was crossed over with the patient's current treatment dose.The study was conducted in three medical centers.

The Objectives:

The primary objectives of the study was to evaluate the pharmacokineticprofile of AP-CD/LD relative to that of IR-CD/LD and to determine therelative pharmacodynamic profiles of the AP-CD/LD vs. IR-CD/LD underreal conditions of use (i.e. derived from at-home diary entries).Another objective was to monitor the subjects for adverse events duringthe study period and to compare the safety of the test products with thereference products.

The secondary objectives of the study was to assess patient andinvestigator global evaluation of, and degree of satisfaction with,AP-CD/LD relative to IR-CD/LD; and to determine the pharmacodynamicprofile of AP-CD/LD relative to that of IR-CD/LD during the PK day.

Pharmacodynamic Evaluation Methods:

ON/OFF chart on PK days by subject and investigator;

UPDRS Motor testing at baseline and at every hour until +16 hours on thePK days;

Self rating of ON/OFF by patient every ½ hour for 16 hours on days 4, 5and 6 and on days 11, 12 and 13;

Total OFF time, total ON time, time to ON, Total time of On withnon-troublesome dyskinesias and of ON with troublesome dyskinesias;

Other pharmacodynamic parameters were allowed to be calculated forexploratory evaluations.

Clinical Study Course Days 1-6 and 8-13

Subjects were randomized to start with either AP-CD/LD or currenttreatment, taken for 6 days at home.

Subjects were asked to fill in an ON/OFF diary on days 4, 5 and 6 and ondays 11, 12 and 13.

Dosing:

Test arm: BID administration of AP-CD/LD 50/375 mg (morning and +8hours). Due to the individuality and variability of treatment of thefluctuating Parkinson's patient the subjects were allowed (if necessary)to take up to 3 daily add-on doses of IR-CD/LD on days 1-6 or 8-13 ofthe “at home” treatment. Each additional “add-on” doses was limited toeither ½ tablet of Dopicar (12.5/125 mg CD/LD) or ¼ tablet of Dopicar(6.25/62.5 mg CD/LD). All add-on doses were documented in the subject'sdaily diary.

Control arm: The current, individual treatment of each subject.

No additional CD/LD was allowed after midnight of days 6 and 13 (priorto the PK day).

Days 7 and 14

Subjects were confined to the clinic from the previous night for theduration of the day until the next morning (36 hours).

Dosing:

Test arm: BID AP-CD/LD, No add-on doses were allowed during the PK day(during the blood sampling), since they will interfere with thepharmacokinetic profile. Additional IR-CD/LD was allowed only after thelast blood sample was taken.

Control arm: 4×¾ tablet of Dopicar (18.75/187.5 mg CD/LD) at 0, +4, +8,+12 hours.

On day 7 (at the clinic), pharmacodynamic evaluations were conducted forthe first 16 hours by an assessor using the UPDRS part III. The patientdocumented ON/OFF times for 16 hours. The objective of these UPDRS andON/OFF evaluations on days 7 and 14 were to evaluate thepharmacokinetics/pharmacodynamic correlation. Each subgroup was crossedover with an equal-dose of current individualized levodopa treatment ina randomized manner.

Post Study Medical Evaluation:

Within 7 days after the last PK day (days 15-22), the subjects underwentpost-study medical evaluation including blood and urine testing.

AP-CD/LD 50/375 mg, Designed for Advanced Stage PD Patients

Amount/AP-CD/LD (mg) Internal layer Outer (sum of Immediate ReleaseComponent Controlled release two films) capsule coating Layer CD layerCarbidopa 50 Levodopa 375 50 Eudragit S100 52 Eudragit L100 80 26Eudragit L100-55 26 11 Fish Gelatin 104 Propylene glycol 104 KOH 6.6Poloxamer 407 40 5.5 PEG 400 40 3 Titanium Oxide 3 Kollidon VA64 15

Results Pharmacokinetics (PK)

Mean LD plasma concentrations are presented in FIG. 2.

True controlled-release profile of LD has been presented, withsignificantly more stable LD levels, during the 16 waking hours, and infact 24 hours since significant morning levels were achieved.

A clear “flip-flop” kinetics (where Ka is much slower than Ke, hence thecurve reflects the actual Ka) can be seen. LD's absorption phase wasincreased by 6 folds and more, by the AP-CD/LD. BID administration ofAP-CD/LD provided 24 hours coverage of mean LD plasma levels of522-1,710 ng/ml, in comparison to mean LD plasma levels of 91 (or 68—seebelow)—3,377 ng/ml, obtained with four times a-day administrations ofIR-CD/LD, currently on the market (with equidose total daily LD of 750mg, in both arms).

Peak to trough fluctuations (Mean Cmax−Mean Cmin) were statisticallysignificantly reduced, by the AP-CD/LD, to a half. Similarly, peak totrough ratio (mean Cmax/mean Cmin) is reduced by almost sevenfold:

Least-Squares Means¹ Significance³ LD Parameter AP-CD/LD Control Ratio²(p < 0.05) Mean Cmax 2,285 3,999 0.571 0.0055 (ng/mL) Mean Cmin 348 90.93.830 0.0332 (ng/mL) Absolute Peak-to- 1,937 3,908 0.496 0.0023 TroughFluctuation (ng/mL) Peak to trough 6.57 44.00 6.7 ratio ¹Least-squaresarithmetic means. ²Ratio calculated as AP-CD/LD least-squares meandivided by Control least-squares mean. ³Results of the statisticalevaluation by ANOVA (α = 0.05) for the hypothesis of equal treatmenteffects

Mean AUC₀₋₂₄, achieved with the AP-CD/LD was 94.6% of the Mean AUC₀₋₂₄achieved by IR-CD/LD. This calculation is based on the assumption thatLD level at t=24 h is equal to LD level at t=0, in both arms (whereascurrent available controlled release LD products decreasebioavailability to about 75%).

The LD morning plasma levels achieved with the AP-CD/LD arestatistically significantly higher (p=0.0191) than those achieved withthe commercial IR treatment: 522 ng/ml vs. 91 ng/ml.

Pharmacodynamics

In 10 patients who completed the study in accordance with the studyprotocol, a statistically significant decrease in ‘OFF time’ andstatistically significant reduction in the number of doses per day wereachieved. In 80% of these patients, an average reduction of about 35% inthe OFF time (2.96 hours compared to 4.48 hours with their currenttreatment) was achieved, which is statistically significant.

The number of daily doses in this patient group was reduced by half,from 6.0 times per day to 3.2 times per day (namely—BID administrationof AP-CD/LD plus 1.2 add-on doses per day), with a statisticallysignificance. This reduction was obtained due to an effective longacting AP-CD/LD. This achievement addresses one of the current unmetneeds with respect to PD treatment—the daily significant pill burden,which is a result of the very short half-life of LDs preparationscurrently on the market.

Both subjects' and investigators' CGI and GSS evaluations correlatedwith the improvements demonstrated in the various pharmacodynamicsend-points.

Mean Time to ON after First Dose (Day 7)

Mean Time to ON (Hours) Post Morning Dose on Day 7 (N=6)

AP-CD/LD Current Difference Mean Time to 0.64 0.97 −0.33 ON Post MorningDose

The shorter Mean Time to On, with AP-CD/LD, was obtained due to twoattributes:

-   -   Significantly higher LD plasma levels at time 0 (7 AM), due to        the true-controlled release performances of the AP-CD/LDs given        the day before (522.0 vs 90.9 ng/ml, as described above);    -   An efficient IR component of the AP-CD/LD.

The significantly higher morning LD plasma levels provide a veryimportant advantage in the treatment of advanced-stage PD patients.

PK/PD Correlation (Day 7)

A strong correlation was demonstrated in day 7 between LD plasma levelsand ON/OFF and UPDRS data, during the 16 hours' evaluations. Thisvalidates the concept of the strong PK/PD correlation in LD treatment,with respect to the drug's motor complications, as well as the hugeimportance of stabilizing the drug's PK. The graph, presenting thecorrelation of UPDRS score with the blood plasma levels of LD ispresented in FIG. 5. As can be seen from the figure, the UPDRS does notgo above the baseline score, meaning steady improvement in PD symptomsover tested period.

Safety

No significant adverse effects were reported during the study.

Subjects Enrolled:

Duration of Duration LD's Randomization of PD, Treatment, Usual DailyCurrent LD No. Gender Age (years) (years) H&Y Treatment* 301 F 61 19 162.5 Completed the study not per protocol 303 M 75 10 6 2.5 5 × 125 + 100= 725 mg 304 M 77 10 10 2.5 5 × 125 = 625 mg 305 M  84** 12 10 3 4 ×125 + 3 × 100 + 62.5 = 862.5 mg 306 M 62 6 6 2 5 × 125 = 625 mg 307 M 6011 9 3 200 + 8 × 100 = 1,000 mg** 308 M 71 17 15 2.5 5 × 125 = 625 mg309 F 61 Dropped out 310 F 57 13 13 3 6 × 125 = 750 mg 311 M 77 9 6 2.55 × 125 = 625 mg 312 M 64 10 6 2 6 × 125 = 750 mg 313 M 61 8 6 2.5 5 ×187.5 = 937.5 mg *Subject's usual LD treatment, in addition to othermedications. This was also the control arm's treatment in days 4-6 and11-13, for each subject, in general. **Both deviations above werepre-approved by the IRB.

Based on examples 1 and 2, the AP-CD/LD has demonstrated its potentialto a significantly improve LD treatment through:

-   -   Reducing the pills burden;    -   Decreasing wearing OFF;    -   Improving patients' compliance with therapy; and    -   Improving sleep quality and morning akinesia.

Example 3 Pharmacodynamic Evaluation in Fluctuating Patients

The purpose of this study was to evaluate pharmacodynamic changes influctuating PD patients upon treatment with AP-CD/LD 50/375 mg,following three weeks treatment.

Study Objectives:

Primary objectives of the study were to evaluate a change in the totaldaily OFF time (hr) from at home ON/OFF diaries, at week 3 of eachtreatment, between AP-CD/LD and active control; and to assess patientand investigator global evaluation, and degree of satisfaction with,AP-CD/LD relative to current levodopa treatment.

Course of the Study:

The study included multiple dosing for 21 days with the AP-CD/LD crossedover with a similar duration of treatment with the patient's currenttherapy. Both treatment periods included 21 days of treatment out ofwhich the first 14 days were for equilibration (readjusting to thetreatment after the crossover) and the last 4 days were for theevaluation (test period).

Subjects were randomized to start with either AP-CD/LD or currenttreatments. There was no washout period between treatment periods due tothe equilibration period prior to the test periods. The test periodincluded 4 days of treatment. Pharmacodynamics evaluation was based onON/OFF home diaries from 3 days prior to the clinic visit and on UPDRSpart III performed every hour for 6 hours during a clinic visit on thelast day of each test period (days 21 and 42).

Results

In a sub-group of 6 patients the regimen was based on BID AP CD/LD50/375 mg. In this group the Total OFF Time was reduced from 2.9 hourswith the current treatment to 1.2 hours with the AP treatment. Inaddition, a significant reduction (more than threefold) of LD doses wasachieved. The number of LD daily doses in their current treatment armwas 6.6 times a day.

Example 4 Pharmacokinetic Profile of AP-CD/LD 50/500 mg

The purpose of the study was to evaluate the pharmacokinetic parametersof AP-CD/LD 50/500 mg, in healthy volunteers, as single dose versus IRof 2×250 mg LD (Sinemet® 25/250 mg (Merck & Co., Inc.)).

Study Objectives:

The primary objective was to compare the pharmacokinetic profiles of LDand carbidopa, following oral administration of a single-dose of acontrolled-release gastric retentive formulations, with that obtainedfollowing oral ingestion of two consecutive doses of the referenceproduct Sinemet®, taken after a low-medium calorie meal.

The secondary objective was to monitor the subjects for adverse eventsduring the study period and to compare the safety of the testformulation with the reference product.

Study Design:

Single center, randomized, single-dose, open label, two-way, comparativecrossover study. The wash-out period between study sessions will be atleast 7 days.

Course of the Study:

Pretreatment—50 mg of carbidopa three times daily on the three daysprior to each dnrug administration was administered to diminish or avoidthe ADRs that were anticipated in LD-naïve patients.

Dosing—the dosing of either 2×Sinemet® 25/250 mg or 1×AP-CD/LD 50/500 mgwas performed in a cross-over manner with washout period of 1 week.

Formulation of AP-CD/LD 50/500 mg

Amount/AP-CD/LD (mg) Internal Outer Immediate layer (sum of ReleaseControlled two Levodopa Component release films) Layer CD layerCarbidopa 50 Levodopa 430.0 70.0 Eudragit S100 14.3 50.9 Eudragit L100109.9 Eudragit L100-55 12.7 11 Fish Gelatin 50.9 Polyox WSR-205 5.9 KOH2.1 Poloxamer 407 9.5 5.5 Poloxamer 124 62.1 14.9 PEG 400 62.1 35.7Sodium Starch 50.0 Glycolate

Results:

The pharmacokinetic profile is presented in FIG. 3.

The PK parameters are summarized in table below:

Least-Squares Means ¹ 90% Confidence Interval ³ Parameter Test ReferenceRatio ² Lower Upper AUG 0-t (ng-hr/mL) 10693 14047 0.761* 0.615 0.907AUCinf (ng-hr/mL) 12426 14123 0.880 0.486 1.274 Cmax (ng/mL) 1951 40620.480* 0.153 0.808 Tmax (hour) 4.67 4.83 0.966 — — Ke (1/hour) 0.28290.4041 0.700 — — T½ (hour) 5.15 1.76 2.927 — — ¹ Least-squares geometricmeans for In-transformed data. ² Ratio calculated as Test least-squaresmean divided by the Reference least-squares mean. ³ Confidence intervalon the ratio. *Comparison was detected as statistically significant byANOVA (α = 0.05).

The results show that high LD concentrations can be reached withAP-CD/LD 50/500 mg, concentrations sufficient to provide the need foradvanced PD patients.

Example 5 Typical Exemplary Menu Employed in the Examples Above Version1

Breakfast (−30 min) 529 Kcal 51% fat

2 slices of bread, butter (40 g), 8 olives, cookies (40 g), tea(decaffeinated, 1 spoon of sugar).

Lunch (+5 hours) 530 Kcal 40% fat

Salami sandwich (one, approx. 50 g), vegetable salad (120 g), fruitsalad (1 cup)

Snack (+7.75 hours) 190 kcal 49% fat

Plain croissant (50 g)

Dinner (+12 hours) 525 kcal 34% fat

Fried breaded chicken breast (100 g), vegetable salad (120 g), rice (1cup)

Version 2

Breakfast (−30 min) 529 Kcal 51% fat

2 slices of bread, butter (40 g), 8 olives, cookies (40 g), tea(decaffeinated, 1 spoon of sugar).

Lunch (+5 hours) 648-670 Kcal 34% fat

Option 1: Salami sandwiches (two, approx. 100 g), vegetable salad (120g), fruit salad (1 cup)

Option 2: Humus sandwiches (two, approx. 100 g), vegetable salad (120g), fruit salad (1 cup)

Snack (+7.75 hours) 190 kcal 49% fat

Plain croissant (50 g)

Dinner (+12 hours) 525 kcal 34% fat

Fried breaded chicken breast (100 g), vegetable salad (120 g), rice (1cup)

Version 3

Snack at arrival 190 kcal 49% fat

Plain croissant or cookies (50 g), non-caffeinated tea

Lunch (˜+5 hours) 648-670 Kcal 34% fat

Option 1: Salami sandwiches (two, approx. 100 g), vegetable salad (120g), fruit salad (1 cup)

Option 2: Humus sandwiches (two, approx. 100 g), vegetable salad (120g), fruit salad (1 cup)

Snack prior to second dosing of AP 190 kcal 49% fat

Plain croissant (50 g) or cookies, non-caffeinated tea

Version 4

Breakfast (−30 min) 529 Kcal 51% fat

Option 1: 2 slices of bread with butter (40 g) with 1 small Plaincroissant

Option 2: 2 slices of bread with butter (40 g) with Vanilla pudding

Both with tea (decaffeinated, 1 spoon of sugar)

Lunch (˜+5 hours) 648-670 Kcal 34% fat

Option 1: Salami sandwiches (two, approx. 100 g), vegetable salad (120g), fruit salad (1 cup)

Option 2: Humus sandwiches (two, approx. 100 g), vegetable salad (120g), fruit salad (1 cup)

Throughout the Day (Optional)

Cookies and non-caffeinated tea

Those of skill in the art will recognize that numerous modifications andchanges may be made to the exemplary designs and embodiments describedherein and that the invention is not limited to such embodiments.

1-24. (canceled)
 25. A method for the treatment of symptoms ofParkinson's disease in a subject in need thereof, comprising:repetitively administering an accordion pill comprising atherapeutically effective amount levodopa, to the subject in a twicedaily administration regimen of two doses in a day, as a first dose ofthe day and as a second dose of the same day, with an interval of about8 to about 10 hours between the first dose of the day and the seconddose of the same day, with the first dose of the following consecutiveday commencing 24 hours after the first dose of the previous day whereinthe accordion pill comprising levodopa is a multilayered gastroretentivedosage form, folded into a capsule in undulated form, which unfolds uponcontact with gastric fluids.
 26. The method according to claim 25,wherein the accordion pill comprises about 250 mg levodopa, and whereinthe repetitive twice daily administration regimen provides average bloodplasma levels of levodopa of 200-1,000 ng/ml in the subject over a 24hour period following administration of the first dose of the day; orwherein the accordion pill comprises about 375 mg levodopa, and whereinthe repetitive twice daily administration regimen provides average bloodplasma levels of levodopa of 500-1,500 ng/ml in the subject over a 24hour period following administration of the first dose of the day; orwherein the accordion pill comprises about 500 mg levodopa, and whereinthe repetitive twice daily administration regimen provides average bloodplasma levels of levodopa of 700-2,000 ng/ml in the subject over a 24hour period following administration of the first dose of the day. 27.The method according to claim 25, wherein the accordion pill providesabsorption of levodopa into the blood plasma of the subject for about 6to about 14 hours following administration of the accordion pill to thesubject.
 28. The method according to claim 25, wherein the repetitivetwice daily administration regimen further comprises administering tothe subject one or more dosage forms comprising immediate-release orcontrolled-release levodopa.
 29. The method according to claim 25,wherein the repetitive twice daily administration regimen providesstable blood plasma levels of levodopa with an absolute peak-to-troughratio of levodopa blood plasma concentrations below
 7. 30. The methodaccording to claim 25, wherein the repetitive twice daily administrationregimen reduces peak-to-trough fluctuations in the blood plasma levelsof levodopa in the subject by at least 50% in comparison toimmediate-release formulations of levodopa comprising daily equal-doses,administered four times a day.
 31. The method according to claim 25,wherein the repetitive twice daily administration regimen shortens oreliminates total OFF time during waking hours in the subject.
 32. Themethod according to claim 25, wherein the repetitive twice dailyadministration regimen allows faster onset of the ON period in thesubject.
 33. The method according to claim 25, wherein the repetitivetwice daily administration regimen alleviates or eliminates nightlysleep disturbances and daytime sleepiness or drowsiness in the subject.34. The method according to claim 31, wherein the repetitive twice dailyadministration regimen further comprises administering to the subjectone or more add-on dosage forms comprising immediate-release orcontrolled-release levodopa.
 35. The method according to claim 25,wherein the repetitive twice daily administration regimen producessignificantly high morning levels of levodopa in the blood plasma of thesubject, thereby allowing faster onset of the ON period or shortening ofthe OFF period after the first dose of the day.
 36. The method accordingto claim 35, wherein the repetitive twice daily administration regimenalleviates or eliminates nightly sleep disturbances and daytimesleepiness or drowsiness in the subject.
 37. The method according toclaim 38, wherein the accordion pill comprises about 250 mg levodopa and50 mg of carbidopa, and wherein the repetitive twice dailyadministration regimen provides an average blood plasma level oflevodopa of 200-1,000 ng/ml in the subject over a 24 hour periodfollowing administration of the first dose of the day; or wherein theaccordion pill comprises about 375 mg levodopa and 50 mg of carbidopa,and wherein the repetitive twice daily administration regimen providesan average blood plasma level of levodopa of 500-1,500 ng/ml in thesubject over a 24 hour period following administration of the first doseof the day; or wherein the accordion pill comprises about 500 mglevodopa and 50 mg of carbidopa, and wherein the repetitive twice dailyadministration regimen provides an average blood plasma level oflevodopa of 700-2,000 ng/ml in the subject over a 24 hour periodfollowing administration of the first dose of the day.
 38. The methodaccording to claim 25, wherein the accordion pill further comprises anamount of carbidopa sufficient to provide carbidopa blood plasma levelssufficient to adequately prevent peripheral levodopa side effects in thesubject.
 39. The method according to claim 25, wherein the repetitivetwice daily administration regimen provides stable blood plasma levelsof levodopa in the subject with values of area-under-the-curve over 24hours and a relative bioavailability that is not less than 85% relativeto the values obtained from immediate-release formulations comprisingdaily equal-doses administered four times a day.
 40. (canceled)
 41. Themethod according to claim 26, wherein the accordion pill comprises about375 mg levodopa, and wherein the repetitive twice daily administrationregimen provides an average blood plasma level of levodopa of 500-1,500ng/ml in the subject over a 24 hour period following administration ofthe first dose of the day.
 42. The method according to claim 26, whereinthe accordion pill comprises about 375 mg levodopa, and wherein thetwice daily administration regimen after multiple administrationsprovides an average blood plasma level of levodopa of 500-1,500 ng/ml inthe subject over a 24 hour period following administration of the firstdose, and wherein the repetitive twice daily administration regimenreduces total OFF time during waking hours of not less than 50% incomparison to the total OFF time associated with immediate-releaseformulations comprising daily equal-doses of levodopa, administered fourtimes a day.
 43. A method for the treatment of symptoms responsive tolevodopa in a subject in need thereof over a nocturnal period,comprising administering to said patient an accordion pill comprisinglevodopa, wherein said accordion pill is administered to the subject ator before bedtime; wherein said accordion pill is administered to thesubject no later than 5 hours from the administration of the lastlevodopa dose; wherein said administration provides improvement in sleepquality in said subject over the night following administration; andwherein the accordion pill comprising levodopa is a multilayeredgastroretentive dosage form, folded into a capsule in undulated form,which unfolds upon contact with gastric fluids.
 44. The method accordingto claim 43, wherein said administration further alleviates oreliminates the symptoms of morning akinesia or morning dystonia.
 45. Themethod according to claim 38, wherein the accordion pill comprises about50 mg to about 75 mg of carbidopa.